Snow caster



R. J. BACON SNOW CASTER Nov. 18, 1969 Filed April 28, 1967 3Sheets-Sheet 1 W KO mm mu VR m ATTORNEY Nov. 18, 1969 R. J. BACON3,478,448

SNOW CASTER Filed April 28, 1967 3 Sheets-Sheet 2 3 INVENTOR.

4 Y aoesa J. aAcqu 1 I E] 3 [a ATTORNEY Nov. 18, 1969 R. J. BACON3,473,448

snow CASTER Filed April 28, 1967 3 Sheets-Sheet 5 INVENTOR. ROGER J.BACON BY 1M4). M

ATTORNEY United States Patent US. CI. 37-43 Claims ABSTRACT OF THEDISCLOSURE A machine for removing snow that employs a scoopshaped shieldmovable through the snow with its open end forward. A rotatable shaftmounted transversely in said shield, a pair of ribbon-type angersmounted for rotation on said shaft, an impeller fixed to the center ofsaid shaft coaxially with and between said augers, an impeller housingextending outwardly from within said shield and overlying said impeller,a pair of semicircular baffie plates forming portions of the sides ofsaid impeller housing and extending between said impeller and saidangers so that 40 percent of the side ingress to said impeller isblocked, means for rotating said impeller at a speed seven times therotational speed of said augers, at a predetermined forward shield speedthe capacities of said augers and said impeller having the relationshipof I=A+Y where I equals the total capacity of the impeller, A equals theamount of snow that the augers move into the impeller and Y is theamount of snow fed directly into the impeller due to the forwardmovement of the shield, but wherein the total capacity of the augers isgreater than the quantity A and part of their capacity is blocked bysaid bafiles and recirculated as a quantity X.

BACKGROUND OF THE INVENTION Field of the invention The field of theinvention is automatic snow removal equipment and, more particularly,snow casters of the rotary auger-type.

Description of the prior art Heretofore prior auger-type snow casters ofwhich applicant is aware have provided no baflles between the augers andimpeller to confine the impeller and to control the discharge capacityof the impeller. Without baffies these prior machines would blast lightpowdery snow out through the front of the shield rather than through thedischarge chute and under heavy damp snow conditions would receive snowfrom the augers at too great a rate such that the impeller would beoverloaded and stall.

SUMMARY The present invention is directed to an improved snow casterthat em loys baffies to partially confine the impeller. In a morespecific form of the invention the baffles are arranged to cover acertain percentage of the side ingress into the impeller, whichpercentage is balanced with the snow displacement capacity of the augersand the snow discharge capacity of the impeller. To some degree, thebalance may be achieved by the design capacities of the augers or theimpeller or by the size of the baffles. This relationship is establishedby the formula I =A+Y where I equals the total discharge capacity of theimpeller, A equals the amount of snow moved into the impeller by theangers, and Y equals the amount of snow fed directly into the impellerdue to the forward movement of the shield. A blocked quantity of snow Xrepresents some percentage of the total capacity of the augers above thequantity A that is fed to the impeller. The baflles provide proper3,478,448 Patented Nov. 18, 1969 confinement of the impeller toelfectively handle all types of snow and regulate the quantity of snowfed to it by the augers so that the impeller is always operated at theproper capacity.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a side elevation of a snowcaster embody ing the invention.

FIGURE 2 is an enlarged section taken along the line 22 of FIGURE 1.

FIGURE 3 is a schematic perspective looking into the front of the snowcaster showing the various paths of the snow therein.

FIGURE 4 is an enlarged vertical section taken along the line 44 ofFIGURE 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT In general, the preferredembodiment of the invention is best shown in FIGURES 1 and 3 in which asnow caster 10 i shown attached to a vehicle 11 which pushes the snowcaster over the ground. The snow caster comprises a scoop-shaped shield12 having a set of vertical end walls 13. The shield is supported abovethe ground by a pair of shoes or skids 14 adjustably fastened to thevertical end walls. Two augers 15 and an impeller 16 are rotatablymounted in the shield. A discharge chute 17 communicates with an opening18 (FIG. 4) in the upper rear portion of the shield. As the snow casteris moved through snowcovered' terrain, snow is scooped into the shieldand is fed either directly into the front of the impeller 16 or into theside of the impeller by the augers and is discharged through thedischarge chute. The scoop-shaped shield 12 is best shown in FIGURES 3and 4 and includes a rear curved portion 23 in which is provided theopening 18. Adjustably fastened to the bottom of the rear curved portionis a scraper bar 24. A curved wear plate 25 is fastened to the inside ofthe rear curved portion and provides protection against stones or otherhard objects picked up by the scraper bar. The shield also has anupwardly and outwardly diverging top wall 26. The vertical end walls arefastened to both the rear curved portion and the top wall to provideadditional rigidity to the shield. An impeller housing 29 is fastened tothe inside surface of the top wall of the shield and is provided with apair of semi-circular plates or baffles 30 having curvatures thatconform closely to the curvature of the rear curved portion of theshield. The bafiles are welded to the rear curved portion with theirdiametrical edges inclined upwardly at an angle of approximately 30. Thepurpose of the baffles will be described in more detail below. A coverplate 31 is fastened to the top curved edges of the baflles forming acompartment partially enclosing the impeller.

'IEhe augers 15 are best shown in FIGURES 2 and 3 and are the reverse ofone another. Each auger has a hollow cylindrical core 32 that isjournaled for rotation by inner and outer bearings 33, respectively, ona rotatable shaft 34. The rotatable shaft 34 is journaled for rotationin the vertical side walls 13 by bearings 35. Each auger also isprovided with a generally helical ribbon or flight 36 that is supportedon the core in spaced relation thereto by a plurality of radial supports37. A sprocket 38 is fixed to one end of each core and is driven by achain 39. The chain is trained around a drive sprocket 3811 that iscoupled to a drive shaft 40 through a conventional slip drive 41. Thedrive shaft is coupled to a conventional gear box 42 which is powered bythe vehicle 11 through a shaft 43. Power from the vehicle turns thesprockets 38 to rotate both of the augers at the same speed.

Theimpeller 16 is best shown in FIGURES 2 and 4 and includes fourequally spaced, triangular channel members or blades 46. The blades havereplaceable tips 47 at their outer ends and are fastened to a hub 48that is keyed to the rotatable shaft 34. The blades are also fastenedtogether for extra rigidity by bolts 49. A sprocket 50 is connected tothe left-hand, as viewed in FIGURE 2, end of the rotatable shaft 34 andis driven by a chain 51. The chain 51 is also trained around a drivesprocket 50a that is keyed to the drive shaft 40. As can be readily seenthe sprockets 50 and 50a are of approximately the same diameters whereasthe sprocket 38 is considerably larger than the sprocket 38a such thatthe augers are rotated substantially slower than the impeller. Thisratio is approximately 7 to 1.

For optimum snow removal in an auger-type snow caster it is necessary tohave the impeller remove under varying conditions as much snow as it iscapable of handling. To accomplish this a necessary relationship betweenthe quantity of snow being fed into the impeller and its discharge rateis required. It is necessary, therefore, to adjust the various factorscontributing to this balance for a normal depth of snow and a normalvehicle speed and then by the balance effect optimum snowremoval forconditions varying from normal.

As an example, assume the normal vehicle speed and thus the forwardspeed of the scoop-shaped shield 12 is three-quarters of a mile per hourand the depth of snow to be removed is 18 inches. The desired impellerspeed is 700 r.p.m. and, at the aforementioned ratio of 7 to 1, theauger speeds are 100 r.p.m. With a shield length of 44 inches and thebafiies 30 set to block approximately 40 percent of the entrance to theimpeller blades, the dimensions of the augers should be determined todisplace a total capacity of 6.53 cubic ft. per sec. This total capacityis equal to the amount of snow seen by the augers, 5.22 cubic feet persec. for the above snow depth, width and shield speed, plus an arbitrarypercentage, assume 25 percent or 1.31 cubic feet per sec. for overloadcapacity. The recirculated quantity X is some arbitrary percentage lessthan the overload capacity and may for the example be assumed to bepercent or .522 cubic feet per sec. A, the quantity fed to theimpellers, is thus (5.22-.522) or 4.698 cubic feet per sec. Y is equalto the quantity of snow seen by the impeller directly or .825 cubic feetper sec. for the above snow depth, width and shield speed. Thus, theimpeller will be designed to handle a capacity of A-+Y or 4.698+.825equal to 5.523 cubic feet per second at a rotational speed of 700revolutions per minute. The designs for the augers and impeller toobtain the desired capacities are easily determined by one skilled inthe art. Also, the size of the baffles may be varied slightly to attaina proper balance; however, it is best to set the blockage at 40 percentto effect optimum impeller discharge.

In operation, the vehicle is moved forward and as the snow is capturedby the shield the impeller is fed by the snow Y (FIG. 3) through whichit passes and by the snow displaced by the augers. Excess snow over thequantity A that is displaced by the auger is recirculated in thedirection of the arrows shown in FIGURE 3 as the quantity X. With thehigh speed ratio of 7 to 1 the impeller imparts a substantial velocityto the snow thus throwing it through the discharge chute and clear ofthe vehicle. When the vehicle speed is decreased or increased or if thedepth of snow should increase or decrease the .4 variations, except forthe variations in the small quantity Y, are taken up by the recirculatedquantity X. Thus, as can be readily seen the invention permits effectiveremoval of snow in a variety of conditions without stalling or operatingthe impeller at a substantial undercapacity.

It is understood that the invention is capable of variation andmodification without departing from the principle thereof and thus theinvention should be limited only by the scope and proper interpretationof the claims.

The invention having been described that which is claimed as new anddesired to be covered by Letters Patent is:

1. A snow caster comprising a longitudinally extending scoop-shapedshield, a rotatable impeller mounted substantially centrally of saidshield, augers rotatably mounted in said shield on either side of saidimpeller and formed to feed snow to said impeller, said impeller andsaid augers being mounted in said shield for rotation about a commonaxis, and plates carried by said shield and located between the innerends of said augers and said impeller for limiting the amount of snowfed to said impeller by said augers, said plates having their diametricedges inclined upwardly from the rear wall of said shield and spacedslightly above said common axis.

2. A snow caster defined by claim 1 wherein said plates coverapproximately 40% of the side ingress to said impeller.

3. The snow caster defined by claim 1 further including means forrotating said impeller and said augers, and wherein said impeller isrotated approximately seven times faster than said augers.

4. The snow caster defined by claim 1 wherein said shield has a rearcurved portion and an upper top wall outwardly diverging from said rearcurved portion, said plates are semi-circular, are of the same curvatureas said rear portion, and are fastened to said shield with the curves ofthe plates nestled in said rear portion, and wherein the diametric edgesof said plates are inclined upwardly from said rear portion and arespaced slightly above said longitudinal axis.

5. The snow caster defined by claim 1 wherein said impeller is rotatedapproximately 700 r.p.m. and said auger is rotated approximately r.p.m.

References Cited UNITED STATES PATENTS 3,078,603 2/1963 Ertsgaard et al.2,871,585 2/1959 Merry et al. 3743 3,305,949 2/1967 Holley 37432,731,739 1/ 1956- Miller.

FOREIGN PATENTS 823,673 10/ 1937 France. 1,030,851 5 8 Germany.

627,518 9/ 1961 Canada.

181,203 10/ 1962 Sweden.

729,860 3/ 1966 Canada.

ROBERT E. PULFREY, Primary Examiner ENGENE H. EICKHOLT, AssistantExaminer US. Cl. X.R, 302-50

